In his 2002 novel, "Wish You Were Here," Stewart O'Nan performed a daring feat: Writing about a week in the life of a nothing-special middle-class family, he strived to be epic yet casual, combining the precision of John Updike's Rabbit novels with the homey language of O'Nan's friend Stephen King. Its 500-plus pages of close character study might have sometimes felt ungainly, but its ambition was undeniable.

"Emily, Alone," O'Nan's admirable sequel, initially seems made of smaller stuff. It's half the length of "Wish You Were Here" and instead of detailing a host of characters it exclusively focuses on Emily Maxwell, the elderly matriarch of the Pittsburgh clan. There's some early drama when her sister-in-law, Arlene, suffers a mild stroke at their favorite breakfast place. But Emily isn't wringing her hands as she stands watch in the hospital room. "Here there was a constant stream of people recapping last night's TV shows, or helping them solve the crossword," Emily observes, almost cheered by the new rhythm set by this turn of events.

That's the book's goal: To show life's persistence without the grim fatalism or spry attitude that define so many fictional portraits of the aged. O'Nan's episodic chapters inhabit Emily's thoughts on a host of quotidian things: thank-you notes, housekeeping, driving, watching television, listening to the radio. But O'Nan gives each small experience an emotional heft, and he's supremely skilled at revealing Emily's emotional investment in every small change in her life. When her dog has to make a trip to the vet, it's enormous, and when she catches a cold it's as much opportunity as illness -- a chance to interact with others anew. "Being sick," O'Nan points out, "was news."

Still, this is primarily a book about death, or about approaching it. Emily keeps tabs on Arlene, puts her own financial house in order, ponders the friends and loved ones she's buried. Yet those gestures don't make "Emily, Alone" feel funereal so much as honest. Emily is a tremendous noticer of things: The details in others' homes, the ways her children avoid tough subjects, the emotional and literal baggage she's picked up over the years. And old age, for her, is an inevitable but not somber process of letting go of that clutter. "As she grew older, she found it easier to part with the tokens of their past," O'Nan writes as Emily gathers up her and her late husband's possessions for a rummage sale. "She was done storing things in the hope that someone would love them as much as she did." The tone of that sentence -- plainspoken but brassy, somber but straight-talking -- infuses this entire nervy, elegant book.